In order for radio frequency (RF) switching circuitry to operate correctly when an RF switch path is open and an RF switch path is closed, contacts provided by one or more switches in a switch device need to be appropriately biased. For example, if the switching device employs one or more field effect transistors (FET) as switches, the gate contact, the drain contact, the source contact and the body contact of each of the FETs has to be biased appropriately. Generally, at least one control signal is provided to control the closing and the opening of the RF switch path provided by the switch device. From this control signal, bias and control networks typically provide the appropriate biases to the contacts.
Traditional switch bias and control networks use separate resistor networks to bias the gate contact and the body contact of each of the FETs in the switch device. A principal drawback of this configuration is that there is significant loading of the RF switch path provided from the bias and control networks. This can degrade the quality (Q) factor of the switch device. This can also degrade a Q factor of RF circuitry that employs the switch device to provide switching. For example, the switch device may be employed in digital programmable capacitor arrays within a tunable RF filter structure. The loading provided from the resistor networks thus can degrade the Q factor of the tunable RF filter structure. As such, configurations of RF switching circuitry is needed that can provide less loading and thus higher Q factors.